Joseph T Libby's first wife

On page 542 of Volume 1 of the Libby Family in America, it says that my great-great grandfather Joseph Libby "married Hannah J, dau. of Joseph Lovett of Hudson, and had children, Ida and Hannah." On page 266 it says "he lives in Waterloo, Iowa with a wife and three children." Joseph married Sarah Adcock in Texas in 1870, and at that time he was a widower.In 1881 he was in Waterloo with three children, one of whom was my great-grandfather Edward Ellison Libby. Does anyone possibly have any information as to what happened to his first wife and their daughters? Thanks! Maggie Olson